TWI586641B - Bimetallic lanthanide complex, fabricating method and use thereof, polycarbonate and method of manufacturing polycarbonate - Google Patents

Description

Double lanthanide metal complex, preparation method thereof, Use thereof, method for producing polycarbonate and polycarbonate

The present invention relates to a biguanide metal complex, and more particularly to a biguanide metal complex which can be used as a catalyst to produce polycarbonate and a process for the preparation thereof.

Due to the unique electronic structure of the lanthanide metal elements, the materials derived from the lanthanide metal elements have always been closely related to the development of the global high-tech industry. Because of its wide range of uses, such as photoelectric, permanent magnet, catalysis, superconductivity, green energy and In the field of ceramics and other fields, these materials are often referred to as "industrial vitamins", "mother of new materials" or "golden 21st century". The industry dedicated to the development of lanthanide metal elements is also known as "sunrise." industry".

In addition, the global warming problem is becoming more and more serious. Carbon dioxide (CO ₂ ) is the main greenhouse gas, but in the current trend of developing renewable biological resources, rich, non-toxic and non-flammable carbon dioxide is considered to have One of the potential and low carbon sources. Therefore, based on environmental awareness, existing researches often use carbon dioxide as a carbon source to co-polymerize with epoxide, which can consume greenhouse gas carbon dioxide, and secondly produce polycarbonate that is easily biodegradable and environmentally friendly ( Polycarbonate, PC) polymer material.

For the copolymerization of such carbon dioxide and epoxide, various metal catalysts including complexes such as aluminum, chromium, cobalt, iron, magnesium and zinc have been developed, which have better catalytic activity, but Air or water sensitivity increases the difficulty of the process. Furthermore, in the prior research, although a lanthanide metal element is used as a catalyst for such a copolymerization reaction, it is not suitable for a subsequent process, and it is difficult to be widely used.

In view of this, how to develop a catalyst having catalytic activity and excellent controllability of co-polymerization of carbon dioxide and epoxide by utilizing the particularity of lanthanide metal elements is a goal of subsequent research and development.

One embodiment of one aspect of the present invention is to provide a biguanide metal complex. The diterpene metal complex comprises a diterpenoid metal ion and a plurality of ligands respectively coordinated to the diterpenoid metal ion, and each ligand has a formula as shown in formula (i) or formula (ii) One structure: , The oxygen atom, the nitrogen atom and the oxygen ion are coordinated to the coordination position of the diterpene metal ion, R ¹ may be a hydrogen atom or an alkoxy group, and R ² may be a pyridyl group or a phenyl group.

The biguanide metal complex according to the foregoing embodiment may further comprise a plurality of co-ligands, each of which is coordinated with a diterpenoid metal ion and each independently selected from water, methanol or acetic acid. root.

The big lanthanide metal complex according to the above embodiment, wherein the ratio of the aforementioned diruthenic metal ion to the aforementioned acetate may be 1:2 to 1:1.

A big lanthanide metal complex according to the foregoing embodiment, which may have a structure as shown in any one of formulas (I) to (III): Wherein L _n is a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion or a cerium ion.

One embodiment of another aspect of the present invention is to provide a method of preparing the aforementioned big lanthanide metal complex. First, a mixing step is performed to form a mixed solution containing a lanthanide-containing metal salt, the aforementioned ligand, and at least one solvent. Next, a standing step is performed to allow the mixed solution to stand for a reaction time to form a big lanthanide metal complex.

A method of producing a biguanide metal complex according to the foregoing embodiment, wherein the reaction time of the aforementioned standing step may be from 1 day to 2 weeks.

Accordingly, the present invention provides a simple process for preparing a bismuth metal complex, and the bismuth metal complex is air-stable, which not only reduces the cost but also increases the range of application in subsequent applications.

One embodiment of a further aspect of the present invention is to provide a use of the above-described biguanide metal complex as a catalyst for conducting copolymerization of one of carbon dioxide and an epoxide.

Another embodiment of another aspect of the present invention is to provide a method of producing a polycarbonate. First, an epoxide, carbon dioxide, and the aforementioned big lanthanide metal complex are provided. Next, a copolymerization reaction is carried out to obtain a There is a mixture of polycarbonates and a purification step is carried out to obtain a polycarbonate.

The method for producing a polycarbonate according to the above embodiment, wherein the reaction temperature of the aforementioned copolymerization reaction may be greater than or equal to 80 ° C and less than or equal to 150 ° C.

The method for producing a polycarbonate according to the above embodiment, wherein the molar ratio of the epoxide to the diterpene metal complex described above may be from 500:1 to 2000:1.

Another embodiment of one aspect of the present invention is to provide a polycarbonate produced by the foregoing method.

Thereby, the present invention can carry out the copolymerization reaction of carbon dioxide and epoxide by using the above-mentioned big lanthanide metal complex as a catalyst without using an external cocatalyst, thereby not only increasing the application range of the lanthanoid metal, but also reducing the application range. The cost of such applications is a breakthrough in the application of existing technologies.

The Summary of the Invention is intended to provide a simplified summary of the present disclosure in order to provide a basic understanding of the disclosure. This Summary is not an extensive overview of the disclosure, and is not intended to be an

S100‧‧‧ steps

S102‧‧‧Steps

S200‧‧‧ steps

S202‧‧‧Steps

S204‧‧‧Steps

The above and other objects, features, advantages and experimental examples of the present invention will be more apparent and understood. The description of the drawings is as follows: FIG. 1 is a flow chart showing the preparation method of the big lanthanide metal complex of the present invention. Figure 2 is a flow chart showing a method of manufacturing the polycarbonate of the present invention; Fig. 3 is a hydrogen nuclear magnetic resonance spectrum chart of the purified polycarbonate in Experimental Example 4 of the present invention; and Fig. 4 is a hydrogen nuclear magnetic resonance spectrum chart showing the mixture after the reaction in Experimental Example 6 of the present invention.

The various embodiments of the invention are discussed in more detail below. However, this embodiment can be applied to various inventive concepts and can be embodied in various specific ranges. The specific embodiments are for illustrative purposes only and are not limited by the scope of the disclosure.

An object of the present invention is to provide a biguanide metal complex comprising a diterpenoid metal ion and a plurality of ligands respectively coordinated to a diterpenoid metal ion, and each ligand has a formula One of the structures shown in (i) or (ii): , . The lanthanide metal ion may be a lanthanum ion (Lathanide, La ³⁺ ), a cerium ion (Cerium, Ce ³⁺ ), a cerium ion (Praseodymium, Pr ³⁺ ), a cerium ion (Neodymium, Nd ³⁺ ), or a cerium ion. Ions (Promethium, Pm ³⁺ ), barium ions (Samarium, Sm ³⁺ ), barium ions (Europium, Eu ³⁺ ), barium ions (Gadolinium, Gd ³⁺ ), barium ions (Terbium, Tb ³⁺ ), barium Ions (Dysprosium, Dy ³⁺ ), strontium ions (Holmium, Ho ³⁺ ), cesium ions (Erbium, Er ³⁺ ), strontium ions (Thulium, Tm ³⁺ ), strontium (Ytterbium, Yb ³⁺ ) or strontium ions (Lutetium, Lu ³⁺ ), the invention is not intended to be limited thereto.

R ¹ may be a hydrogen atom or an alkoxy group, and R ² may be a pyridyl group or a phenyl group. Specifically, the alkoxy group may be a C1 to C10 alkoxy group, and the aforementioned pyridyl group or phenyl group may be a hydrogen atom-substituted pyridyl group or a phenyl group. In addition, the oxygen atom, the nitrogen atom and the oxygen ion of the formula (i) and the formula (ii) are used to coordinate the coordination position with the diterpenoid metal ion, in particular, when R ¹ is an alkoxy group At the time of the base, the oxygen thereon also provides a coordination position, that is, the ligand is at least a three-bud base, and more preferably a four-bud base.

More specifically, the foregoing big lanthanide metal complex comprises at least two ligands, that is, the above-mentioned big lanthanide metal complex can be constructed from a diterpenoid metal ion and a didentate. The ligands may be the same or different. For example, the above two ligands may all have the structure shown in formula (i), or may be all of the structures shown in formula (ii), or one of them (i) The structure shown is the structure shown by the formula (ii).

In addition to the foregoing ligands, the biguanide metal complex of the present invention may further comprise a plurality of co-ligands, each of which coordinates with a diterpenoid metal ion. That is to say, the big lanthanide metal complex can be combined with more than one co-ligand to satisfy its coordination number or balance its overall charge, and the plurality of co-coordination groups are independent and can be water and methanol. Or one or more of acetate. At this time, based on the coordination position provided by the ligand and the co-ligand, each of the lanthanide metal ions of the bismuth metal complex of the present invention may be The structure of the eight-coordinate to nine-coordinated structure will be described in detail in the subsequent embodiments, and will not be described herein.

Thereby, the big lanthanide metal complex provided by the present invention can appropriately modify the central lanthanide metal ion by the design of the ligand and the electronic effect generated by the co-ligand, thereby greatly improving the subsequent The effect of the application.

Next, please refer to FIG. 1 , which is a flow chart showing a method for preparing a biguanide metal complex according to the present invention, which comprises steps S100 and S102. As shown in FIG. 1, step S100 is a mixing step of mixing a lanthanide-containing metal salt, a ligand, and at least one solvent to form a mixed solution, wherein the lanthanide-containing metal salt ion may comprise an isolated electron pair, in other words, The anion in the lanthanide-containing metal salt may be used as a source of the co-ligand, or the lanthanide-containing metal salt may be a hydrate. In this case, the anion and the water molecule in the lanthanide-containing metal salt may be co-coordinated. The source of the base. Further, the solvent is selected in such a manner that the lanthanide-containing metal salt and the ligand are sufficiently dissolved, and the subsequently prepared bismuth-based metal complex is precipitated, so that the solvent of the present invention may be, for example, methanol ( Methanol, MeOH), acetonitrile (Acetonitrile, MeCN), dimethylformamide (DMF) or a mixture thereof, but the invention is not intended to be limited thereto.

In addition, a deprotonated alkali treatment may be performed in the mixed solution to accelerate the formation of a big lanthanide metal complex suitable for subsequent X-ray diffraction analysis, but the present invention does not add a deprotonated base. For the sake of necessity, it is first stated. The structure of the ligand, the functional group thereon and the preparation method thereof will be further described in the following examples, and therefore will not be described herein.

Next, performing a standing step as shown in step S102, The foregoing mixed solution is allowed to stand for a reaction time to form a big lanthanide metal complex. Further, the reaction time of the step S102 is from 1 day to 2 weeks. Furthermore, although not shown in FIG. 1, a filtering step may be further included between step S100 and step S102 for removing impurities in the mixed solution, thereby preventing impurities from affecting the big lanthanide metal complex. The crystal grows or is subsequently analyzed for accuracy.

The big bismuth metal complex according to the present invention and the preparation method thereof have been roughly described. As described above, the structure of the above-mentioned big lanthanide metal complex of the present invention will be described by way of Examples 1 to 3 and Comparative Examples. And the preparation method thereof, but it is not intended to limit the scope of the invention to be protected, and is described first.

[Double lanthanide metal complex and its preparation] [Example 1]

In the embodiment 1, the structure of the biguanide metal complex of the present invention and a method for producing the same will be further described in detail. First, in step S100, the to 0.0675 g (0.25 mmol) of the ligand and 0.103 g (0.25 mmol) of dysprosium (III) acetate tetrahydrate _{(Dy (OAc) 2 .4H 2} O) 20 Methanol and 10 ml of acetonitrile are used as a solvent to form a mixed solution, wherein the ligand of Example 1 has a structure represented by formula (i), and R ^{1 is} specifically a methaneoxy group, and R ^{2 is} specifically benzene. The base, that is, the ligand used in Example 1, is a ligand having O, O, N, O-tetra buds.

As described above, although not shown, after the step S100, the mixed solution may be further deprotonated with 0.07 ml of 0.5 mmol of triethylamine (NEt ₃ ) and subjected to a filtration step of the mixed solution. Remove any impurities that may be present.

Next, as shown in step S102, the filtered mixed solution was allowed to stand at room temperature for two days. Finally, the precipitated pale yellow crystals are collected and washed with diethyl ether to obtain a biguanide metal complex (wherein the lanthanide metal is ruthenium), and the bismuth metal complex of the present invention has air stability. It can be used when it is stored in a normal state for subsequent applications.

At this time, it was confirmed by X-ray diffraction that the big lanthanide metal complex of Example 1 had a structure represented by the formula (I): As shown in the formula (I), the big lanthanide metal complex formed by the two ligands and the four acetate structures is centered on two ruthenium metal ions each independently nin-coordinated.

[Embodiment 2]

In Example 2, the first 0.0675 g (0.25 mmol) of the ligand and 0.103 g (0.25 mmol) of dysprosium (III) acetate tetrahydrate _{(Dy (OAc) 2 .4H 2} O) to 30 ml of methanol is used as a solvent to form a mixed solution, wherein the ligand of the embodiment 2 also has a structure represented by the formula (i), and R ^{1 is} also specifically a methaneoxy group, except that it is different from the embodiment 1. In the second embodiment, R ^{2 is} specifically a pyridyl group, that is, the ligand used in the embodiment 2 is a ligand having O, O, N, O-tetra buds.

As described above, although not shown, after the step S100, the aforementioned mixed solution may be further subjected to a filtration step to remove impurities which may be present therein. Next, as shown in step S102, the filtered mixed solution was allowed to stand at room temperature for one day. Finally, the precipitated pale yellow crystals are collected and washed with diethyl ether to obtain a biguanide metal complex, and the biguanide metal complex is also air-stable and can be stored under normal conditions for later application. .

At this time, it was confirmed by X-ray diffraction that the big lanthanide metal complex of Example 2 had a structure represented by the formula (II): As shown in formula (II), the bis-ruthenium metal complex composed of two ligands, two buds of bridge bristle and two methanol structures is independently octagonal ruthenium metal ions. as a center.

[Example 3]

Different from Example 1 or Example 2, the ligand (0.06 g, 0.25 mmol) added in Example 3 has the structure represented by the formula (ii), and R ^{1 is} specifically a hydrogen atom. And R ^{2 is} specifically a phenyl group, that is, the ligand used in Example 3 is a ligand having O, N, O-trio.

Further, in Example 3, 25 ml of acetonitrile and 5 ml of dimethylformamide were used as a solvent, and the mixed solution was allowed to stand for five days, and the steps of collecting and washing the precipitated crystals were carried out, but the details are detailed. As in Embodiment 1, no further details are provided herein. At this time, the big lanthanide metal complex of Example 3 has a structure of the formula (III): As shown in formula (III), the big lanthanide metal complex of Example 3 is composed of two ligands, four acetates and two waters, and each of them is a nine-coordinated ruthenium metal ion. as a center.

[Comparative Example]

Different from Example 2, in the comparative example, the co-ligand of the biguanide metal complex is nitrate, which has a structure as shown in formula (IV):

[Use of a double lanthanide metal complex as a catalyst]

Please refer to FIG. 2, which is a flow chart showing a method for manufacturing a polycarbonate according to the present invention, which includes step S200, step S202, and step S204. First, as shown in step S200, an epoxide, carbon dioxide, and the above-described two-lanthanide metal complexes of Examples 1 to 3 and the comparative examples are provided as a catalyst for copolymerization of carbon dioxide and an epoxide, and a ring The oxide has the structure shown in formula (a): Wherein m is an integer of 1 to 2, and R ³ may be a hydrogen atom, an alkyl group or an alkenyl group, and the invention is not intended to be limited thereto. Next, as shown in step S202, the carbon dioxide and the epoxide are subjected to a copolymerization reaction in the presence of a biguanide metal complex to prepare a polycarbonate-containing mixture. Finally, a purification step is carried out to obtain the desired polycarbonate as shown in step S204.

The specific operations and conditions of each step will be further described in detail by Experimental Example 1 to Experimental Example 7 and comparative experimental examples, and the use of the big lanthanide metal complex provided by the present invention as a catalyst for carbon dioxide and epoxide is disclosed. The effect that can be achieved by copolymerization to produce polycarbonate.

[Experimental Example 1]

First, the big lanthanide metal complex of Example 1 as a catalyst was added to a high pressure reactor, and after hot extraction for 2 hours, it was cooled to room temperature. After that, the carbon dioxide is slowly introduced, and the epoxy cyclohexane which has been previously dehydrated is quickly added. It should be noted that the epoxide used in Experimental Example 1 to Experimental Example 7 and the comparative experimental examples is epoxycyclohexane, but the present invention is not intended to be limited thereto. In addition, the real In the first example, the molar ratio of the epoxycyclohexane to the catalyst was 500:1. Next, the carbon dioxide is charged to a specified pressure of 500 pounds per square inch (psi), the intake valve is closed, and the agitation is slowly dissolved to dissolve the carbon dioxide into the reactants, and the pressure gauge is observed and carbon dioxide is added to the aforementioned specified pressure. After the pressure was constant, the reaction was carried out at 100 ° C for 24 hours.

After the end of the reaction, the reactor ice bath was cooled to normal temperature and slowly depressurized, and dissolved in an appropriate amount of dichloromethane to obtain a mixture, and a small amount of the mixture was subjected to hydrogen nuclear magnetic resonance spectroscopy (subsequently referred to as ¹ H-NMR). Finally, a purification step was carried out to obtain a purified polycarbonate, and further subjected to ¹ H-NMR analysis using the purified polycarbonate. In particular, by ¹ H-NMR spectroscopy, it was confirmed that the big lanthanide metal complex of Example 1 was used as a copolymer of a catalyst for copolymerization of carbon dioxide and epoxycyclohexane, based on ¹ H. - NMR spectroscopy analysis of the proportion of polycarbonate in the aforementioned mixture (referred to as "% copolymer") and the proportion of carbonate segments in the purified polycarbonate (referred to as "% carbonate") 1 is shown.

Other uses of the big lanthanide metal complex of the embodiment 1 of the present invention is a catalyst for copolymerization of carbon dioxide and epoxycyclohexane, such as productivity (Turnover number, referred to as "TON"), catalytic activity (Turnover frequency) The number average molecular weight (referred to as "M _n ") of the polycarbonate obtained by "TOF" and its polycarbonate is also shown in Table 1. Among them, the productivity depends on the number of moles of epoxycyclohexane consumed by each mole of catalyst, and the catalytic activity is determined by dividing the estimated productivity value by the reaction time.

[Experimental Example 2]

In Experimental Example 2, the copolymerization reaction of carbon dioxide and epoxycyclohexane was carried out by using the big fluorene metal complex of Example 1 as a catalyst. However, unlike Experimental Example 1, in Experimental Example 2, the molar ratio of epoxycyclohexane to catalyst was 1000:1, and the reaction time of the copolymerization reaction was 96 hours, and the remaining steps and reaction parameters were The experimental example 1 is the same, and will not be described again here, and the related measurement data is organized as shown in Table 1.

[Experimental Example 3]

In Experimental Example 3, the biguanide metal complex of Example 2 was used as a catalyst for the copolymerization reaction of carbon dioxide and epoxycyclohexane, and the remaining steps and reaction parameters were the same as in Experimental Example 1, and the description thereof will not be repeated here. And the relevant measurement data is organized as shown in Table 1.

[Experimental Example 4]

In the same manner as in Experimental Example 4, the biguanide metal complex of Example 2 was used as a catalyst for the copolymerization reaction of carbon dioxide and epoxycyclohexane, but Experimental Example 4 differs from Experimental Example 1 in the epoxy of Experimental Example 4. The molar ratio of cyclohexane to catalyst is 1000:1, and the reaction time of the copolymerization reaction is 96 hours. The rest of the steps and reaction parameters are the same as those of Experimental Example 3, and will not be described here, and the relevant measurement data will be sorted out. As shown in Table 1.

[Experimental Example 5]

In Experimental Example 5, the double bismuth metal of Example 2 was also used. The complex compound is used as a catalyst for the copolymerization reaction of carbon dioxide with epoxycyclohexane, but it differs from Experimental Example 3 in that the molar ratio of the epoxycyclohexane to the catalyst in Experimental Example 5 is 2000:1, and The reaction time of the copolymerization reaction was 144 hours. The remaining steps and reaction parameters are the same as those in Experimental Example 3, and are not described here again, and the relevant measurement data are organized as shown in Table 1.

[Experimental Example 6]

The catalyst used in the experimental example 6 is the biguanide metal complex of the embodiment 3 of the present invention, and the remaining steps and reaction parameters are the same as those of the experimental example 1, and will not be described again, and the relevant measurement data is as shown in Table 1. Show.

[Experimental Example 7]

The catalyst used in Experimental Example 7 was also the biguanide metal complex of Example 3 of the present invention, except that in Experimental Example 6, the molar ratio of the epoxycyclohexane to the catalyst in Experimental Example 7 was 1000:1, and the reaction time of the copolymerization reaction was 48 hours. The remaining steps and reaction parameters are the same as those in Experimental Example 6, and will not be described again here, and the relevant measurement data are organized as shown in Table 1.

[Comparative Example 1]

Different from Experimental Example 1, in Comparative Experimental Example 1, the big lanthanide metal complex of the comparative example was used as a catalyst for copolymerization of carbon dioxide and epoxycyclohexane, and the remaining steps and reaction parameters were as in Experimental Example 1. The same, will not be described here, and the relevant measurement data is organized as shown in Table 1.

Please refer to Table 1. First, it can be seen from the comparative experimental examples that when the big lanthanide metal complex of the comparative example is used as a catalyst for copolymerization of carbon dioxide and epoxycyclohexane, the conversion of epoxycyclohexane is low. At 5%, that is, the big lanthanide metal complex of the comparative example hardly produced a catalytic effect on the aforementioned copolymerization reaction.

On the other hand, in Experimental Example 1 and Experimental Example 2, when the biguanide metal complex of Example 1 of the present invention was used as a catalyst, 69% conversion of epoxycyclohexane was achieved in 24 hours, and the reaction was carried out. Only less than 10% of the cyclic carbonate by-product was formed in the latter mixture, and the content of the carbonate segment in the purified polycarbonate was 89%. What's more, when the molar ratio of epoxycyclohexane to catalyst is adjusted to 1000:1 and reacted for 96 hours, the conversion of epoxycyclohexane can reach 84%, except that the molecular weight can be 12200g/mol. In addition to the polycarbonate, only less than 10% of the cyclic carbonate by-products in the reacted mixture The content of the carbonate segment in the polycarbonate produced and purified is also 90% or more. That is to say, the big lanthanide metal complex of the first embodiment of the present invention has a good selectivity for the catalysis of carbon dioxide and epoxycyclohexane copolymerization, and can obtain a polycarbonate having a molecular weight of 10,000 g/mol or more. ester.

Next, in Experimental Example 3 to Experimental Example 5, the big fluorene-based metal complex of Example 2 of the present invention was used as a catalyst for copolymerization of carbon dioxide and epoxycyclohexane. As shown in Table 1, in Experimental Example 3 to Experimental Example 5, the molar ratio of the cyclohexene oxide to the catalyst was increased, and the selectivity of the copolymerization reaction was also increased. For example, in Experimental Example 4, 1% of the cyclic carbonate by-product was formed when the reaction mixture was measured, but as shown in Fig. 3, ¹ H-NMR of the purified polycarbonate was shown. The spectrum shows that the signal at 4.65 ppm belongs to the methine proton of the polycarbonate, and the signal at 3.58 ppm and 4.42 ppm belongs to the methine proton of the terminal group (OCH(CH ₂ ) ₄ )CHOH), but at 3.2. No obvious signal was observed in the 3.5 ppm range, so it can be analyzed that the content of the carbonate segment in the purified polycarbonate is still higher than 99%, that is, the double lanthanide metal of the second embodiment of the present invention is misaligned. The material has good selectivity for the catalysis of carbon dioxide and epoxy cyclohexane copolymerization. Further, from Experimental Example 5, when the molar ratio of the epoxycyclohexane to the catalyst was increased to 2000:1, the productivity was over 1600, and the molecular weight of the polycarbonate produced was as high as 17,000 g/mol.

Finally, please refer to Experimental Example 6 to Experimental Example 7. The above two experimental examples are the use of the biguanide metal complex of Example 3 of the present invention as a catalyst for copolymerization of carbon dioxide and epoxycyclohexane. As shown in Table 1, when the big lanthanide metal complex of Example 3 was used as a catalyst, the conversion of the cyclohexene was about 85% in either Experimental Example 6 or Experimental Example 7, and both were Has good selectivity. For example, please refer to FIG. 4, which is a hydrogen nuclear magnetic resonance spectrum of the mixture after the reaction in Experimental Example 6 of the present invention. As shown in Fig. 4, from the ¹ H-NMR spectrum of the mixture after the reaction, the signal of the carbonate segment in the polycarbonate is 4.6 ppm to 5.0 ppm, and the polycarbonate is in the range of 3.3 ppm to 3.7 ppm. The signal of the ether segment, which is a signal of a cyclic carbonate at 3.1 ppm to 3.2 ppm, shows that less than 4% of the cyclic carbonate by-products were produced in Experimental Example 6. Further, although not shown, it can be further understood that the content of the carbonate segment in the purified polycarbonate is still higher than 90% after analysis, that is, the biguanide metal complex of Example 3 of the present invention The catalysis for the copolymerization of carbon dioxide with epoxycyclohexane also has good selectivity.

Further, from Experimental Example 7, it was found that when the biguanide metal complex of Example 3 of the present invention was used as a catalyst for the above reaction, a polycarbonate having a molecular weight of up to 22,200 g/mol can be obtained.

In summary, the double lanthanide metal complex provided by the present invention has air stability and is simple in process. When the bismuth metal complex is used as a catalyst for copolymerization of carbon dioxide and epoxide Moreover, a certain catalytic activity and productivity can be maintained without an external cocatalyst, and a polycarbonate having a molecular weight higher than 10000 g/mol can be obtained, so that the invention can be more favorable for subsequent application, in addition to reducing the process cost. .

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and those skilled in the art may not deviate from the essence of the present invention. The scope of protection of the present invention is defined by the scope of the appended claims.

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Claims (8)

A big lanthanide metal complex comprising a diterpenoid metal ion and a plurality of ligands and a plurality of co-ligands respectively coordinated to the diterpenoid metal ion, wherein each of the ligands has its own One of the structures shown in formula (i) or formula (ii): An oxygen atom, a nitrogen atom and an oxygen ion are coordinated to a coordination position of the diterpene metal ion, R ¹ is a hydrogen atom or an alkoxy group, R ² is a pyridyl group or a phenyl group, and the co-coordination The base system does not contain nitrate and is combined with one of water or methanol and acetate, and the ratio of the diterpene metal ion to the acetate of the biguanide metal complex is 1:2 to 1 :1. The biguanide metal complex according to claim 1, which has a structure as shown in any one of formulas (I) to (III): Wherein L _n is a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion, a cerium ion or a cerium ion. A method for preparing a biguanide metal complex according to claim 1, comprising: performing a mixing step of forming a lanthanide-containing metal salt, one of the ligands and at least one solvent Mixed solution; A standing step is performed to allow the mixed solution to stand for a reaction time to form the big lanthanide metal complex. The method for producing a biguanide metal complex according to claim 3, wherein the reaction time of the standing step is from 1 day to 2 weeks. A use of a biguanide metal complex according to any one of claims 1 to 2, wherein the biguanide metal complex is used for carbon dioxide and epoxide A total of polymerization. A method for producing a polycarbonate, comprising: providing an epoxide, carbon dioxide, and a biguanide metal complex as described in any one of claims 1 to 2; performing a copolymerization reaction to obtain A mixture comprising one of the polycarbonates; and a purification step to obtain the polycarbonate. The method for producing a polycarbonate according to claim 6, wherein a reaction temperature of the copolymerization reaction is greater than or equal to 80 ° C and less than or equal to 150 ° C. Polycarbonate as described in claim 6 A manufacturing method, wherein one of the epoxide and the big lanthanide metal complex is added in a molar ratio of 500:1 to 2000:1.